Coupling method
The invention relates to a new method of determining the presence, absence or characteristics of an analyte. The analyte is coupled to a membrane. The invention also relates to nucleic acid sequencing.
1. A method for detecting polynucleotides, comprising:
(a) providing a membrane in which is present a nanopore that provides a channel through the membrane, wherein the membrane is coupled to a tethering group;
(b) contacting the membrane, in an ionic solution, with polynucleotides, wherein following contact with the membrane the polynucleotides are tethered to the membrane via the tethering group; and
(c) applying a potential difference across the membrane and detecting a polynucleotide using the nanopore, from among the polynucleotides tethered to the membrane,
wherein the membrane is coupled to the tethering group prior to contacting with the polynucleotides.
2. The method according to claim 1 , wherein the membrane is an amphiphilic layer, a lipid bilayer, or a solid state layer.
3. The method according to claim 1 , wherein the tethering group comprises a hydrophobic anchor.
4. The method according to claim 3 , wherein the hydrophobic anchor is a lipid, fatty acid, sterol, carbon nanotube, or amino acid.
5. The method according to claim 3 , wherein the hydrophobic anchor is capable of embedding in the membrane.
6. The method according to claim 1 , wherein the polynucleotide is tethered transiently to the membrane.
7. The method according to claim 1 , wherein the polynucleotide is detected based on ion flow through the nanopore that is measured via an electrical means.
8. The method according to claim 1 , wherein the nanopore is a protein nanopore, optionally wherein the protein nanopore is derived from Msp or α-hemolysin (α-HL).
9. The method according to claim 1 , wherein the nanopore comprises a molecular adaptor that mediates interaction of the polynucleotide with the nanopore.
10. The method according to claim 1 , wherein the nanopore is coupled to a polynucleotide binding protein, which is optionally an exonuclease or a polymerase.
11. The method according to claim 1 , wherein the polynucleotide is detected based on ion flow through the nanopore that is measured by measuring a current passing through the nanopore.
12. The method according to claim 1 , wherein the polynucleotide comprises a target polynucleotide.
13. The method according to claim 12 , wherein the method comprises digesting the target polynucleotide to provide a fragment and the fragment sequence is determined.
14. The method according to claim 1 , wherein the tethering group comprises a polypeptide.
15. The method according to claim 1 , wherein the tethering group comprises a linker.
16. The method according to claim 15 , wherein the linker comprises a polynucleotide, polyethylene glycol, polysaccharide, or polypeptide.
17. The method according to claim 1 , wherein the polynucleotide is present in the solution of (b) at a concentration of about 0.001 pM to about 1 nM.
18. The method according to claim 1 , wherein the rate of interaction of the molecules of the polynucleotide with the nanopore is increased as compared to the rate of interaction of molecules of the polynucleotide with the nanopore in the absence of the tethering group.
19. The method according to claim 1 , wherein an effective concentration of the polynucleotide at the nanopore is increased as compared to the concentration of the polynucleotide in the solution of (b).
20. The method according to claim 1 , wherein a single nanopore providing an ion channel through the membrane is present in the membrane.